See main article: 2018 Davis Cup.
The Asia/Oceania Zone was the unique zone within Group 3 of the regional Davis Cup competition in 2018. The zone's competition was held in round robin format in Hanoi, Vietnam, from 2 to 7 April 2018. The two winning nations won promotion to Group II, Asia/Oceania Zone, for 2019.
Date: 2–7 April, 2018
Location: Mỹ Đình Sports Complex, Hanoi, Vietnam (indoor hard)
Format: Round-robin basis. One pool of 4 teams (Pool A) and one pool of 5 teams (Pool B). The winner of Pool A will play-off against the runner-up of Pool B and the winner of Pool B will play-off against the runner-up of Pool A to determine which two nations will be promoted to Asia/Oceania Zone Group II in 2019.
| Pot | Nation | Rank1 | Seed |
|---|---|---|---|
| 1 | 67 | 1 | |
| 73 | 2 | ||
| 2 | 86 | 3 | |
| 91 | 4 | ||
| 3 | 92 | 5 | |
| 93 | 6 | ||
| 4 | 99 | 7 | |
| 103 | 8 | ||
| 114 | 9 |
Standings are determined by: 1. number of wins; 2. number of matches; 3. in two-team ties, head-to-head records; 4. in three-team ties, (a) percentage of sets won (head-to-head records if two teams remain tied), then (b) percentage of games won (head-to-head records if two teams remain tied), then (c) Davis Cup rankings.
| Placing | A Team | Score | B Team | |
|---|---|---|---|---|
| Promotional | 3–0 | |||
| Promotional | 0–2 | |||
| 5th | colspan=2 | |||
| Relegation | 0–3 | |||
| Relegation | 2–1 |